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Applied Dose (applied + dose)
Selected AbstractsLocally delivered rhTGF-,2 enhances bone ingrowth and bone regeneration at local and remote sites of skeletal injuryJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2001Dr. Sumner The purposes of the present study were to determine if recombinant human transforming growth factor-beta-2 (rhTGF-,2) enhances bone ingrowth into porous-coated implants and bone regeneration in gaps between the implant and surrounding host bone. The implants were placed bilaterally for four weeks in the proximal humeri of skeletally mature, adult male dogs in the presence of a 3-mm gap. In three treatment groups of animals, the test implant was treated with hydroxyapatite/tricalcium phosphate (HA/TCP) and rhTGF-,2 in buffer at a dose per implant of 1.2 ,g (n = 6), 12 ,g (n = 7), or 120 ,g (n = 7) and placed in the left humerus. In these same animals, an internal control implant treated only with HA/TCP and buffer was placed in the right humerus. In a non-TGF-, treated external control group of animals (n = 7), one implant was treated with HA/TCP while the contralateral implant was not treated with the ceramic. In vitro analyses showed that approximately 15% of the applied dose was released within 120 h with most of the release occurring in the first 24 h. The TGF-, treated implants had significantly more bone ingrowth than the controls with the greatest effect in the 12 ,g/implant group (a 2.2-fold increase over the paired internal control (P = 0.004) and a 4-fold increase over the external control (P < 0.001)). The TGF-, treated implants had significantly more bone formation in the gap than the controls with the greatest effect in the 12 and 120 ,g groups (1.8-fold increases over the paired internal controls (P = 0.003 and P = 0.012, respectively) and 2.8-fold increases over the external controls (P < 0.001 and P = 0.001, respectively)). Compared to the external controls, the internal control implants tended to have more bone ingrowth (1.9-fold increase, P = 0.066) and had significantly more bone formation in the gap (1.7-fold increase, P = 0.008). Thus, application of rhTGF-,2 to a porous-coated implant-stimulated local bone ingrowth and gap healing in a weakly dose-dependent manner and stimulated bone regeneration in the 3-mm gap surrounding the contralateral control implant, a site remote from the local treatment with the growth factor. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Dermal delivery of desmopressin acetate using colloidal carrier systemsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2005Melkamu Getie Recently, the transdermal route has received attention as a promising means to enhance the delivery of drug molecules, particularly peptides, across the skin. In this work, the skin penetration profiles of desmopressin acetate from a colloidal system (water-in-oil microemulsion) and an amphiphilic cream, a standard formulation, were determined using Franz diffusion cells and compared. In the case of the microemulsion, the total percentages of dose obtained from different skin layers (stratum corneum to subcutaneous tissue) were 3.30 ± 0.67, 7.37 ± 2.43 and 15.54 ± 2.72 at 30, 100 and 300 min, respectively. Similarly, 5.19 ± 0.96, 8.04 ± 0.97 and 14.4 ± 5.15% of the dose applied was extracted from the skin treated with the cream. About 6% of the applied dose reached the acceptor compartment from the microemulsion instead of 2% from the cream within 300 min. The concentration of drug that penetrated into the upper layers of the skin was higher from the cream than from the microemulsion at all time intervals. On the other hand, a higher amount of drug was found in the deeper skin layers and in the acceptor compartment from the microemulsion. [source] Effect of plant phenolics, tocopherol and ascorbic acid on oxidative stability of pork pattiesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2009Lindsey Haak Abstract BACKGROUND: There is great interest in the use of naturally occurring antioxidants to delay oxidation in meat products. The effect of rosemary extract (RE), green tea extract (TE), tocopherol, trolox, ascorbic acid (AA) and ascorbyl palmitate (AP), at levels of 50,200 ppm of antioxidant components, on colour (CIE L*a*b*), lipid (TBARS) and protein oxidation (thiol groups) in fresh, frozen and cooked pork patties during illuminated chill storage was investigated. Individual components of RE and TE were also tested. RESULTS: RE, TE, AP, tocopherol and trolox equally inhibited lipid oxidation in fresh and frozen patties, whereas for cooked patties RE was most effective. AA stimulated lipid oxidation. No dose effect in the range of 50,200 ppm was found for fresh and frozen patties, whereas for cooked patties higher doses of RE and TE more efficiently prevented lipid oxidation. Protein oxidation was hardly influenced by antioxidant treatment. Colour stability decreased as follows: tocopherol, AA and AP > RE and TE > trolox. Antioxidant properties of the extracts and their major antioxidant components were comparable. CONCLUSION: The relative effect of the antioxidants depends on the oxidation parameter assessed, the applied dose and the hydrophilic/lipophilic character. Copyright © 2009 Society of Chemical Industry [source] Application of Insect Repellents by Travelers to Malaria Endemic AreasJOURNAL OF TRAVEL MEDICINE, Issue 4 2006Yvonne Thrower MSc Background The use of insect repellents applied to the skin is always encouraged in those visiting malaria endemic areas. There are a number of factors contributing to the efficacy of insect repellents in the field and an important factor contributing to their longevity relates to the applied dose. This study investigated the dose of insect repellent that travelers might normally apply to the skin. Methods Subjects were asked to apply a product they had purchased to the arms and neck, and the dose applied (mg/cm2) was calculated. The study was conducted using three different populations; 74 travelers to malaria endemic areas visiting pharmacies to purchase repellents before they left the UK, 23 travelers on safari in India, and 24 on safari in Kenya. Results There was a significant difference in the mean applied arm dose of product (mg/cm2) [p < 0.001, analysis of variance (ANOVA)]; UK 1.15 (SD 0.29), India 0.96 (SD 0.23), and Kenya 1.34 (SD 0.54). Higher concentrations were achieved on the neck area. Few of the participants in the field trial used long-sleeved shirts at night. Even using 50% wt/vol repellent products, 32% in the Kenya and 25% in the India, study achieved a dose of active ingredient less than 0.5 mg/cm2. Conclusion These pilot studies would indicate that travelers tend to apply below the optimal concentration of active ingredient of repellent as might be suggested by mathematical models. [source] Long-term after-effects of fertilisation on the restoration of calcareous grasslandsAPPLIED VEGETATION SCIENCE, Issue 2 2008N.A.C. Smits Question: What are the long-term implications of former fertilisation for the ecological restoration of calcareous grasslands? Location: Gerendal, Limburg, The Netherlands. Methods: In 1970, ten permanent plots were established in just abandoned agricultural calcareous grassland under a regime of annual mowing in August. From 1971 to 1979, two different fertiliser treatments were applied twice a year to a subset of the plots (artificial fertiliser with different proportions of nitrogen and phosphorus). The vegetation of the plots was recorded yearly and vegetation biomass samples were taken for peak standing crop and total amounts of nitrogen, phosphorus and potassium. Species composition and floristic diversity were analysed over the research period (1970,2006) and between the treatments, including the use of multivariate techniques (Detrended Correspondence Analysis). Results: In terms of species number, there is a clear optimum 10 to 20 years after fertilisation has been terminated. Afterwards, there is a slow decrease; no new species appear and species of more nutrient-rich conditions gradually disappear. For the fertilised plots that received a relatively high proportion of N, effects are found only in the first years, whereas, for the plots that received a relatively high proportion of P, long-term after-effects are found in species composition, peak standing crop, total amounts of phosphorus in biomass, and in soil phosphorus data. Conclusions: The effect of artificial fertiliser with a large amount of nitrogen disappears in less than ten years when mown in August, including removal of the hay. This is a promising result for restoration of N-enriched calcareous grasslands, as the applied dose of nitrogen in this experiment largely exceeds the extra input of nitrogen via atmospheric deposition. Application of fertiliser with a large amount of phosphorus, however, has effects even more than 25 years after the last addition. There are no prospects that this effect will become reduced in the near future under the current mowing management. [source] Felbamate in Experimental Model of Status EpilepticusEPILEPSIA, Issue 2 2000Andrey M. Mazarati Summary: Purpose: To examine the putative seizure-protective properties of felbarnate in an animal model of self-sustaining status epilepticus (SSSE). Methods: SSSE was induced by 30-min stimulation of the perforant path (PPS) through permanently implanted electrodes in free-running male adult Wistar rats. Felbarnate (FBM; 50, 100, and 200 mg/kg), dizepam (DZP; 10 mg/kg), or phenytoin (PHT; 50 mg/kg) were injected i.v. 10 min after SSSE induction. Electrographic manifestations of SSSE and the severity of SSSE-induced neuronal injury were analyzed. Results: Felbamate injected during the early stages of SSSE (10 min after the end of PPS), shortened the duration of seizures in a dose-dependent manner. Total time spent in seizures after FBM and 290 ± 251 min (50 mg/kg), 15.3 ± 9 min (100 mg/kg), and 7 ± 1 min (200 mg/kg), whereas control animals spent 410 ± 133 min seizing. This effect of FBM was stronger than that of DZP (10 mg/kg, 95 ± 22 min) and comparable to that of PHT (50 mg/kg, 6.3 ± 2.5 min). In the applied doses, FBM (200 mg/kg) was more effective than PHT (50 mg/kg) or DZP (10 mg/kg) in shortening seizure duration and decreasing spike frequency, when administered on the pleateau of SSSE (injection 40 min after the end of PPS). Anticonvulsant action of FBM was confirmed by milder neuronal injury compared with control animals. Conclusions: Felbamate, a clinically available AED with a moderate affinity for the glycine site of the NMDA receptor, displayed a potent seizure-protective effect in an animal model of SSSE. These results suggest that FBM might be useful when standard AEDs fail in the treatment of refractory cases of SE. [source] | ||||||||||